Roll Number:
Thapar Institute of Engineering & Technology
Department of Computer Science & Engineering
End Semester Examination
B. E. (III Year): Semester-I (2022-23)
(CSBS)
Date: 15/12/2022
Time: 3 Hours, M. Marks: 40
Course Code: UCT513
Course Name: Machine Learning
Time: 9:00 to 12:00 P.M.
Name Of Faculty: Sushma Jain
Note: Attempt questions and their sub-parts sequentially at one place.
Assume missing data, if any, suitably
Q1
a) With the help of diagram explain supervised, unsupervised and
reinforcement machine learning approaches.
b) Explain the need of backpropagation algorithm in Multilayer Neural
Network.
Q2 a) Explain loss function of linear regression and logistic regression with the help
of equations.
b) Activation functions play an important role in neural network. Justify.
c) Zero initialization of weights is not a good initialization technique in
neural networks. Justify.
d) Cost function which is used for linear regression can't be used for logistic
regression. Justify.
Q.3 a) Differentiate bagging and boosting.
b) Suppose the following set of data with three Boolean input variables
a; b; and c, and a single Boolean output variable K.
,
1
1
0
1
1
0
0
0
/,
0
1
1
,
1
1
1
/,1
1
0
1
0
0
0
0
0
1
0
0
1
0
0
1
1
f)
Given a data tuple having the values '0', '1', and '0' for the attributes
a, b, and c, respectively, what would a Naive Bayesian classification
of the K for the tuple be?
c) Suppose that the dataset in the figure shown below contains two
classes '+' and '-`. The data is randomly split into a training set (90%)
and a test set (10%) to train and evaluate a model. Which classifier
KNN (with K=1) or Naïve Bayes perform better in terms of accuracy.
Justify?
A
Y
+
X
[1]
(4)
(4)
(2)
(2)
(2)
(2)
(2)
(3)
(3)
Suppose the following Table is a distance matrix for six objects.
Initially there are six clusters. Group these clusters in a single cluster
using hierarchical clustering with single link approach. Show all
intermediate results.
E
F
A
B
C
D
3.61
4.24
3.20
A
0.00
0.71
5.66
2.50
0.71
0.00
4.95
3.54
B
2.92
2.50
5.66
4.95
0.00
2.24
1.41
C
3.61
2.92
2.24
0.00
1.00
0.50
D
4.24
1.12
3.54
0.00
E
1.41
1.00
F
3.20
2.50
2.50
0.50
1.12
0.00
Q.5 a) Explain Hidden Markov Model in brief and list its applications.
b) For the below mentioned grocery store transaction data-set, generate
rules using Apriori algorithm. Consider the values of Support=33.34%
and Confidence-60%.
Transaction
Items
ID
T1
HotDogs, Buns, Ketchup
T2
HotDogs, Buns
T3
HotDogs, Coke, Chips
T4
Chips, Coke
T5
Chips, Ketchup
T6
HotDogs, Coke, Chips
Q.4
[2]
(8)
(3)
(5)
Roll Number:
Thapar Institute of Engineering and Technology, Patiala
Department of Computer Science & Engineering
BE- CSBS (VII Semester) EST
UCT723: Cryptology
Dec 14, 2022, 4:30 PM
Time: 03 Hours; MM: 40
Name of Faculty: Dr. Rajkumar Tekchandani
Note: Attempt all questions. Assume missing data if any.
Q1 .a) Distinguish between passive and active security attacks. List some passive
and active attacks.
b) An organization is implementing an electronic voting (e-voting) system to
elect their president. Only the employees of organization are allowed to vote
online at a voting website that the IT department of organization is
implementing. What security attributes are to be considered for the e-voting
system?
(3)
Q2. a) Explain Advanced Encryption Standard (AES) Key Expansion algorithm.
b) Alice encrypted the plain text (in hexadecimal) of 128 bits {54 77 6F 20 4F
6E 65 20 4E 69 6E 65 20 54 77 6F} with the key (in hexadecimal) of 128
bits {54 68 61 74 73 20 6D 79 20 4B 75 6E 67 20 46 75} using Advanced
Encryption Standard-128 and sent the encrypted message to Bob.
i. Find the value of output state matrix ( 4 x 4) after initial Add Round
Key.
ii. Compute the single entry S'(0,0) of mix column transformation state by
multiplying the first row of mix column transformation matrix as
[EB
(3)
[02 03 01 01] with the following sequence of input bytes
(2)
(3)
(4)
9
c3
7 . Use
20
irreducible polynomial as x' + x4 + x3 + x + 1.
Q3. a) What is the key pair of public key and private key in RSA? What is its
significance? Encrypt and decrypt the letter "H" using RSA by choosing two
prime numbers as p = 11 and q = 3?
b) Explain Elliptic curve cryptography (ECC). What is the zero point of an
Elliptic Curve?
c) Consider the Elliptic curve as [E: y2 = x3 + 2x + 2 mod 17] defined over a
field Z17 . If the point P on elliptic curve is (5,1) then find 2P. Also, Prove
that the calculated point 2P lies on Elliptic curve "E".
(4)
(3)
(4)
Q4. Explain Diffie-Hellman Key Exchange Method? User (A) and (B) uses the (4)
Diffie-Hellman Key Exchange technique with a common prime q = 11 and a
primitive root a = 2.
i.
If user A has public key YA = 9, what is A's private key XA?
ii.
If user B has a public key YB = 3, What is the value of shared secret
key K with user A?
Q5.a) What is the basis for Digital signatures? Explain the working of MD5 Hash
function in brief.
(3)
P.T.O
b) Consider the following X.509 certificate and answer the following
(3)
Certificate:
Data:
Version: 3 (0x2)
Sella' Numbei: 1 (Oxl)
I 1111...1.1 ua:i:•
Algut A t Tun: rual'ildtt hits AK all . ypt a gal
Issuer: C=ZA, ST=Western Cape, L=Cape Town, 0=Thawte Consulting cc,
OU-Certification Setvices Division,
CM=Thawte Setvet CA/Emall=server-certs@thawte.com
vutidAty
Not Before: Aug 1 00:00:00 1996 GMT
Not After : Dec 31 23:59:59 2020 GMT
Subject: C=ZA, ST=Western Cape, L=Cape Town, 0=Thawte Consulting cc,
OU=Certitication Services Division,
CN-Thawte Server CA/Email-servet-certsethawte.com
Subject Public Key Info:
Publla Key Alggrathm: rsaIncrypttun
RSA Public Ke•y: (1024 bit)
Modulus (1024 bit):
00:d3:84:50:6e:c8:ff:56:6b:e6:cf:5d:b6:ea:Oc:
68:75:47:a2:aa:c2:da:84:25:fc:a8:f4:47:51:da:
85:b5:20:74:94:86:1e:Of:75:09:e9:08:61:f5:06:
6d:30:6e:15:19:02:e9:52:c0:62:db:4d:99:9e:e2:
6a:Oc:44:38:cd:fe:be:e3:64:09:70:c5:fe:b1:6b:
29:b6:2f:49:c8:3b:d4:27:04:25:10:97:2f:e7:90:
6d:c0:28:42:99:d7:4c:43:de:c3:f5:21:6d:54:9f:
5d:c3:58:el:c0:e4:d9:5b:b0:b8:dc:b4:7b:df:36:
3a:c2:b5:66:22:12:d6:87:0d
Exponent: 65537 ( Ox10001 )
X509v3 extensions:
X509v3 Basic Constraints: critical
CA:TRUE
Signature Algorithm: mti5WathKSAEncryptton
07:f8:4c:69:5c:fb:95:cc:46:ee:85:83:4d:21:30:8e:ca:d9:
a8:6f:49:1a:e6:da:51:e3:60:70:6c:84:61:11:a1:1a:c8:48:
3e:59:43:7d:4f:95:3d:a1:8b:b7:0b:62:98:7a:75:8a:dd:88:
4e:4e:9e:40:db:a8:cc:32:74:b9:6f:Od:c6:e3:b3:44:0b:d9:
8a:6f:9a:29:9b:99:18:28:3b:d1:e3:40:28:9a:5a:3c:d5:b5:
e7:20:1b:8b:ca:a4:ab:86:e9:51:d9:e2:4c:2c:59:a9:da:b9:
b2:75:1b:f6:42:f2:ef:c7:f2:18:f9:89:bc:a3:ff:8a:23:2e:
70:47
i. Who issues the certificate?
ii. Who is the owner of the certificate?
iii. Who generated the digital signature on this certificate, and how can this
signature be verified?
Q6. Explain Quantum cryptography. How information is represented in Quantum (4)
computing? What are various issues related to Quantum cryptography?